Britannica
Sources used in this answer
How do ctenoid scales differ from cycloid scales in flatfishes?
Created from Britannica articles
using AI.
AI can make mistakes, so verify using Britannica articles.
pleuronectiform
Body plan and sexual dimorphism in the common sole (Solea solea) and dusky flounder (Syacium papillosum).
In flatfishes (order Pleuronectiformes), the primary difference between these two types of scales lies in their surface texture and structure:
- Cycloid scales are characterized by a smooth, round, or oval shape. They are thin and typically exhibit visible growth rings on their surface.123
- Ctenoid scales are structurally similar to cycloid scales but are distinguished by the presence of small, comblike teeth or spines along their overlapping, free edges, giving them a rough texture.123
While both types are bony, overlapping plates formed within the dermis, these variations in edge morphology are common features used to describe the integument of various fish species.123